An extremely old, 19th Century specimen, this matrix specimen features a crust of lustrous, interlocked crystals of white to tan "calamine." Calamine is the pre-1900 name for the mineral hemimorphite. This old specimen is from the William Jefferis collection at Carnegie. Jefferis was one of America's greatest mineral collectors of the 19th. Century and his collection formed a huge core to this museum. Overall a fine specimen anyways, with sparkling, brilliantly lustrous crystals covering matrix and dating to the mid to late 1800s. Ex. Carnegie Museum Collection.